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Why Your Health Care Provider Tests Your Blood Sugar

If you don’t have diabetes, and your doctor orders a blood sugar test, what is he or she checking? In adults, a screening blood sugar test is generally used to see whether blood sugar is too high. Often, adults with raised blood sugar don't experience obvious symptoms of diabetes or prediabetes. Catching and treating type 2 diabetes early is important to prevent problems connected to diabetes. According to 2011 statistics from the CDC, about 19 million people have been diagnosed with diabetes, and an additional 7 million Americans have diabetes but have not been diagnosed. At least 79 million people in the U.S. ages 20 and older have prediabetes. In adults, type 2 diabetes accounts for the majority of all diagnosed cases.

Type 2 on the rise

There's an outbreak of type 2 diabetes in America. It can be controlled if more people begin to pay attention to lifestyle choices. Americans eat too much and exercise too little. Some long-term damage to the body, especially the heart and circulatory system, may already be occurring during prediabetes. People with prediabetes are at high risk for developing type 2 diabetes. Studies have shown that people with prediabetes can put off the development of type 2 diabetes by doing several things. They can make changes in their diet, increase their level of exercise, and lose some weight.

Many people don't know what type 2 diabetes is or why doctors are interested in their blood sugar levels. In diabetes, the hormone insulin, made by your pancreas, isn't used properly. Insulin allows your body to use sugar and other food for energy. Blood sugar rises when there isn't enough insulin. It also rises when your body's cells are unable to use what is there.

In type 2 diabetes, your pancreas either does not make enough insulin or your body’s cells aren’t properly using the insulin. This is called insulin resistance. When blood sugar is raised over and over again, the risk of heart attack and stroke increase by up to 4 times. It also greatly raises the risk for kidney disease, along with possible loss of a leg from poor circulation, blindness, and other disorders. Type 2 diabetes is usually diagnosed later in life.

In an alarming trend, we're diagnosing many teens with this type of diabetes. This was almost unheard of 20 years ago. This is thought to be directly related to being extremely overweight, poor diet, and lack of exercise. The American Diabetes Association (ADA) recommends type 2 diabetes screening for children and teens who are overweight and have at least 2 of these risk factors: a family history of diabetes, in a high-risk ethnic group, or have their health care provider see signs of insulin resistance.

According to the ADA, if you're 45 or older and you don’t have risk factors for diabetes, you should get screened every 3 years. If you have risk factors for diabetes, you may need screening tests more often. If you're under 45, you don't need routine screening unless you are overweight or obese, and have another of the risk factors for diabetes.

Risk factors

Risk factors for type 2 diabetes are:

Being older than 45 years

Being over weight or obese (body mass index of 25 or higher)

Having parents or siblings who have diabetes

High blood pressure (140/90 mmHg or higher in adults)

HDL (good) cholesterol of less than 35 mg/dL and/or a triglyceride level of 250 mg/dL or higher

Having had diabetes during pregnancy or giving birth to a baby weighing more than 9 pounds at birth

Having polycystic ovarian syndrome

Having a history of heart disease

Diagnosing diabetes

The ADA now recommends the A1C test for use in the diagnosis of prediabetes and diabetes. The A1C estimates the average blood glucose levels over the previous 3-month period. An A1C level of around 5% is considered normal. An A1C of 6.5% or above shows diabetes.

The A1C test is not more accurate than the fasting plasma glucose test and the 2-hour oral glucose tolerance test. The difference is the AIC test does not require fasting, so it can be measured at any time of the day. Experts hope the convenience of A1C will result in more testing for people who are at risk for diabetes or prediabetes. This would help reduce the number of people with undiagnosed diabetes in the U.S.